The candidate's overall long-term goal is to become an independent investigator with a program of research on snoring and its association with cardiovascular disease and atherosclerosis. On the continuum of severity of sleep-related breathing disorders, snoring is at the mildest end of the spectrum of which obstructive sleep apnea (OSA) is at the more severe end. Although OSA has been associated with cardio/cerebrovascular disease, effects of snoring alone on health outcomes are largely unknown. In addition, most studies on snoring have used questionnaires to measure snoring, emphasizing that an objective validated measurement of snoring is needed. The goals of the proposed research are (a) to determine the objective snoring index that is optimally associated with carotid atherosclerosis, independent of potential cardiovascular confounders, in a case-control study (K99 phase) and (b) to validate the independent association in a large cohort and examine interactions among snoring, OSA, and obesity that are strongly related to carotid atherosclerosis (R00 phase). We have the opportunity to use the Korean Genome Epidemiology Study (KoGES), an ongoing cohort study of Korean middle-aged and older adults, to achieve the research goals. To date, 5,020 randomly selected participants have undergone biennial comprehensive physical examinations that include carotid intima-media thickness and other variables related to cardiovascular risk. During the K99 phase, we will conduct home-based sleep studies for 100 non-apneic snorers and 100 age-, body-mass index-, and gender-matched normal-controls from the KoGES, to measure objective snoring using a portable sleep device. Objective snoring measurement will include (a) the frequency of snoring episodes, (b) the percentage of snoring time during whole sleeping hours, and (c) snoring sound intensity. During the R00 phase, we will do sleep studies and assess snoring in a large cohort that will consist of 800 KoGES participants with different degrees of snoring. Using an existing ongoing large cohort with comprehensive data on participants' health outcomes is a low-cost and very innovative approach to achieving the ultimate goal of the proposed study. There is a substantial infrastructure and the candidate will have access to multiple other elements at no cost, such as carotid IMT, biomarkers, and DNA for future genetic analyses. Measuring snoring objectively in the home environment is methodologically innovative and will facilitate future snoring and nursing research. Given that the Asian population is growing rapidly in the United States, this study will be significant for the health of Asians in the US population To successfully conduct the proposed research and achieve overall long-term career goals, the candidate will actively participate in a training program during the K99 phase on (a) sleep- related breathing disorders, including snoring~ (b) carotid atherosclerosis measure~ (c) ambulatory technologies to objectively measure snoring~ (d) scientific writing, peer revie, and disseminating~ and (e) professional development for career advancement into a faculty position in a nursing school.